Professor Peter Szlosarek

MD, PhD
Professor of Medical Oncology
Group Leader
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Research Focus

My main research interest is in exploring why ASS1 is aberrantly expressed in human cancers and how this knowledge may be exploited for anticancer therapy. I lead an active translational programme from bench to bedside of the arginine-depleting agent ADI-PEG20 in several hard-to-treat cancers including ADAM, TRAP and ATOMIC clinical studies.

Key Publications

Phase 1 dose-escalation study of pegylated arginine deiminase, cisplatin and pemetrexed in patients with argininosuccinate synthetase 1-deficient thoracic cancers. J Clin Onc (2017) 35 (16):1778-785. PMID: 28388291

Arginine Deprivation with Pegylated Arginine Deiminase in Patients with ASS1-Deficient Malignant Pleural Mesothelioma: A Randomized Clinical Trial. JAMA Oncol (2017)3(1):58-60. PMID: 27584578

Prognostic and therapeutic impact of argininosuccinate synthetase 1 control in bladder cancer as monitored longitudinally by PET imaging. Cancer Res (2014) 74(3):896-907. PMID: 24285724

In vivo loss of expression of argininosuccinate synthetase in malignant pleural mesothelioma is a biomarker for susceptibility to arginine depletion. Clin Cancer Res (2006) 12(23):7126-31. PMID: 17145837

Major Funding
  • 2019-2021- Barts Charity, Targeting the stromal compartment of ASS1-deficient mesothelioma, £149,994
  • ATOMIC-meso (Polaris Pharma) and iTRAP (Polaris Pharma/Roche UK) commercial funding 
Other Activities
  • Chair of the NCRI mesothelioma subgroup
  • EORTC lung and melanoma groups
  • Reviewer for national and international journals
  • Grant reviewer for national and international funding agencies
Themes/Keywords
Targeting Tumour Cells Arginine Deprivation Immunotherapy Metabolism Glioma Mesothelioma Centre for Cancer Biomarkers and Biotherapeutics
Research

Arginine, a semi-essential amino acid in humans, is critical for the growth of human cancers, particularly those marked by de novo chemoresistance and a poor clinical outcome. In addition to protein synthesis, arginine is involved in diverse aspects of tumour metabolism, including the synthesis of nitric oxide, polyamines, nucleotides, proline and glutamate.

However, several tumours are unable to produce arginine, due to variable loss of the enzyme argininosuccinate synthetase ASS1, which is necessary for L-arginine synthesis, including: hepatocellular carcinoma, malignant melanoma, malignant pleural mesothelioma, glioma, prostate and renal cancer.

Our lab is exploring why ASS1 is aberrantly expressed in human cancers. We have identified methylation-dependent silencing of ASS1 in several tumours, including mesothelioma, ovarian cancer, lymphoma and bladder cancer, that are sensitive to arginine deprivation.

Preclinical work in the area of arginine degradation is ongoing in several cancers with our national and international collaborators and industry. We are studying the regulation and modulation of ASS1 expression and the role of the proinflammatory microenvironment in arginine auxotrophic cancers, with the long-term aim of developing novel therapeutic strategies incorporating arginine deprivation and ASS1 loss into routine oncological practice.

We conducted the first randomized trial of the arginine-lowering agent, pegylated arginine deiminase (ADI-PEG20, Polaris Pharma) in mesothelioma using ASS1 as a prospective biomarker showing an improvement in progression-free survival (Szlosarek et al, JAMA Oncol 2017). The current TRAP programme has reported potentiation of anti-folates by ADI-PEG20, which has now moved into phase 2/3 testing in a global trial in non-epithelioid mesothelioma called ATOMIC-meso. Further studies are planned of ADI-PEG20 in combination with immune checkpoint blockade based on exciting new data from the lab.

We continue to study the links between inflammation, immunity and metabolism to discover novel therapeutic targets in oncology.

Other Activities
  • Chair of the NCRI mesothelioma subgroup
  • EORTC lung and melanoma groups
  • Reviewer for national and international journals
  • Grant reviewer for national and international funding agencies
Major Funding
  • 2019-2021- Barts Charity, Targeting the stromal compartment of ASS1-deficient mesothelioma, £149,994
  • ATOMIC-meso (Polaris Pharma) and iTRAP (Polaris Pharma/Roche UK) commercial funding 
Recent Publications

Pegargiminase Plus First-Line Chemotherapy in Patients With Nonepithelioid Pleural Mesothelioma Szlosarek PW, Creelan BC, Sarkodie T et al. JAMA Oncology (2024) 10(10)

A randomised phase II trial of niraparib versus active symptom control in patients with previously treated mesothelioma: NERO. Griffiths GO, Griffiths D, Eminton Z et al. Journal of Clinical Oncology (2023) 41(10) tps8600-tps8600

Correction: A role for macrophages under cytokine control in mediating resistance to ADI-PEG20 (pegargiminase) in ASS1-deficient mesothelioma Phillips MM, Pavlyk I, Allen M et al. Pharmacological Reports (2023) 75(10) 753-753

Abstract CT007: Phase 2-3 trial of pegargiminase plus chemotherapy versus placebo plus chemotherapy in patients with non-epithelioid pleural mesothelioma Szlosarek PW, Creelan B, Sarkodie T et al. Cancer Research (2023) 83(10) ct007-ct007

A role for macrophages under cytokine control in mediating resistance to ADI-PEG20 (pegargiminase) in ASS1-deficient mesothelioma Phillips MM, Pavlyk I, Allen M et al. Pharmacological Reports (2023) 75(10) 570-584

Bench-to-Bedside Studies of Arginine Deprivation in Cancer Field GC, Pavlyk I, Szlosarek PW Molecules 28(10) 2150

BAP1 loss is associated with higher ASS1 expression in epithelioid mesothelioma: implications for therapeutic stratification. Barnett SE, Kenyani J, Tripari M et al. Molecular Cancer Research (2023) 21(10) 411-427

179 (PB059) The combination of the metabolism-based targeted therapies ADI-PEG20 and GC7 are a promising strategy for the treatment of malignant pleural mesothelioma Carpentier J, Szlosarek P, Martin SA European Journal of Cancer (2022) 174(10) s64

1643TiP First-in-human dose-escalation and expansion study (MITOPE) to evaluate mitochondrial PRX3 inhibition by RSO-021 in patients with mesothelioma and other advanced solid tumors Dulloo S, Fennell DA, Szlosarek PW et al. Annals of Oncology (2022) 33(10) s1292-s1293

Arginine Deprivation in SCLC: Mechanisms and Perspectives for Therapy Carpentier J, Pavlyk I, Mukherjee U et al. Lung Cancer Targets and Therapy 13(10) 53-66

For additional publications, please click here
Team

Postdoctoral Researchers
Dr Iuliia Pavlyk

Clinical Research Fellows
Dr Matthew Mee, Dr Emily Turner

Biography

I graduated in 1994 from King’s College, London with degrees in Pharmacology, Medicine and Surgery, receiving the Pharmacology and Therapeutics Intercalated BSc Prize and Legg Prize in Surgical Pathology.

I obtained the MRCP in 1997, and subsequently trained in medical oncology at St. George's, Guy’s and St. Bartholomew's Hospitals, completing a PhD on the molecular biology of TNF-α in ovarian cancer and a postdoctoral position in the Centre for Cancer and Inflammation under Prof Balkwill in 2005.

After a substantive NHS oncology consultant post, I rejoined the BCI as a Principal Investigator in 2008. My translational lab program focuses on aberrant tumour arginine metabolism and inflammation and is closely allied to my clinical interests in the treatment of mesothelial, lung and skin cancers.